Are you Cappin' on me?

It was over-heard in a coffee shop directed by one member of staff in a jocular but indignant tone to a colleague.

This OFDer was unfamiliar with the term but not bashful about finding out. It means teasing, or making fun of, which explains the good-natured way in which the apparent recipient of this behavior had delivered the accusitory question.

"How do you spell it?"

"Don't know. Never seen it written before. C-A-P-P-I-N-apostrophe?" came the quizzical reply, as if she suspected the questioner already knew the answer and was trying to catch her out.

It speaks to the organic nature of language that new words are created and become part of an accepted vocabulary even though they've never been seen in written form by people using the term.

This example is merely one of several it transpires, #6 out of some 18 versions given at urban dictionary. The variations in meaning is rather alarming. Be sure you and the recipient share the same interpretation lest the confusion has fatal consequences for it could mean the difference between being teased and being shot.